Conventionally, an external connection bus bar disclosed in Patent Document 1 has been known as an example of an external connection bus bar that is connected to output electrode terminals of a power storage element group. Patent Document 1 discloses external connection bus bars 19B that are connected to electrode terminals of power storage elements on both ends of a power storage element group, in a battery module (power storage module) M1 with a configuration in which a pair of output electrode terminals are the electrode terminals of the power storage elements on both ends. In view of this, the external connection bus bars 19B are held by resin protectors 20 along with bus bars 19 that connect the electrode terminals of the power storage elements.